I’m in the process of revising 10 new daytrips less than 30 minutes from Paris by train to be called Half An Hour From Paris.

As the name implies, La Ferté sous Jouarre is actually two small towns.  La Ferté is in the Marne valley and Jouarre is on a hill about 3 km away. Above is a photo of Martine (standing), the 68-year-old owner of the café Chez Martine in La Ferté. She tells me she is thinking of retiring in two years as she runs it single-handed. We sympathise – it’s an all too familiar story – and then go on to road test my directions for the country walk to Jouarre.

It seems much quicker than when I first did it, as I now know exactly where I am going. There is no need to revisit the Merovingian crypt at Jouarre as I have already photographed it. There is a cloudburst while we are there so we shelter in the deserted giftshop of the Benedictine abbey, the only place which seems to be open, and I end up buying two tiny handmade cards decorated with pressed flowers. Also, some home-made local fruit jellies which are so delicious that we finish the lot. The old nun at the till, on hearing we are about to walk back to La Ferté in the rain, says ‘Quel courage!’ My friend, being Scottish, looks up at the murky grey skies and says ‘It’s clearing up’ and sure enough, after a few minutes the sun comes out and the countryside beneath us is bathed in sparkling light.

We are almost back at La Ferté when I see from the map that there is a promising detour along the Petit Morin river to where it joins the River Marne, which we don’t have time to try out. There is also a protected wood on the other side of the station which I have decided to exclude from the book, as it looks as if a ramble there might take all day and the Merovingian crypt is the point of the visit. But it’s an excellent reason to go back for the fun of it  – and to test out that little detour before I draw my map.